27 May
2011
27 May
'11
7:12 p.m.
On Thu, 26 May 2011 06:59:47 -0700
dwight elvey <dkelvey at hotmail.com> wrote:
Actually, I was thinking, one of the nicer things to
have in general
is a ROM-ICE. Much quiker than blowing EPROMs with test
code.
Over a decade ago (on topic! ;-) ) I build an embedded system around a
8051 derivate. The chip had build in Flash, but needed a programing
adapter to be flashed. So it would have been the typical, compile, pull
chip, "burn" it, put chip back, cycle for testing. Cumbersome.
So I designed the board with external RAM and EPROM. (Harvard
architecture) I made the external EPROM programm memory visible in the
upper 32 kB of data RAM and I used a SRAM chip insted of an EPROM during
developement. I put a simple serial bootloader into the build in flash
of said 8051 derivate. Thus I needed to programm the chip only once.
So developement was:
Assemble.
Put CPU in Reset state. (Via a switch on the target board.)
Enable internal FLASH. (Via a switch on the target board.)
Switch off reset, CPU starts RS232 bootloader from build in FLASH.
Download code into external programm memory by:
cat file.bin > /dev/tty01
Put CPU in Reset state.
Disable internal FLASH.
Switch off reset, CPU starts downloaded code from external SRAM.
Very convenient. Works as well as an EPROM emulator or some JTAG / ISP
stuff.
--
\end{Jochen}
\ref{http://www.unixag-kl.fh-kl.de/~jkunz/}